RADAR DEVICE

• US 20180074181A1
• Filed: 09/04/2015
• Published: 03/15/2018
• Est. Priority Date: 09/29/2014
• Status: Active Grant

• Current Assignee: Panasonic Automotive Systems Company of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: KISHIGAMI, TAKAAKI, MORITA, TADASHI, KOBAYASHI, KIYOTAKA
• Granted Patent: US 10,379,209 B2
• Time in Patent Office: Days
• CPC Class Codes: G01S 13/0209 Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband
• CPC Class Codes: G01S 13/282 using a frequency modulated carrier wave G01S13/286 takes precedence
• CPC Class Codes: G01S 13/284 using coded pulses
• CPC Class Codes: G01S 13/426 Scanning radar, e.g. 3D radar G01S13/66 takes precedence
• CPC Class Codes: G01S 13/524 based upon the phase or frequency shift resulting from movement of objects, with reference to the transmitted signals, e.g. coherent MTi
• CPC Class Codes: G01S 13/582 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 7/282 Transmitters
• CPC Class Codes: G01S 7/288 Coherent receivers
• CPC Class Codes: G01S 7/2883 using FFT processing
• CPC Class Codes: G01S 7/2886 using I/Q processing

Abstract

A radar device includes: a transmission beam controller that selects, every first period, a transmission beam set used for transmission of a radar signal from among a plurality of transmission beam sets each including at least two transmission beam directions; and a radar transmitter that transmits the radar signal in a predetermined transmission period by using the selected transmission beam set, wherein the transmission beam controller switching, every second period within the first period, among the at least two transmission beam directions included in the transmission beam set.

Claims

1. A radar device comprising:

a transmission beam controller that selects, every first period, a transmission beam set used for transmission of a radar signal from among a plurality of transmission beam sets each including at least two transmission beams having different directions; and

a radar transmitter that transmits the radar signal in a predetermined transmission period by using the selected transmission beam set, wherein

the transmission beam controller switches, every second period within the first period, among the at least two transmission beam having different directions included in the selected transmission beam set.

2. The radar device according to claim 1, further comprising:

a receiver that receives a reflected signal which is the radar signal reflected by a target;

a coherent integration processor that performs, every second period, coherent integration with respect to the received reflected signal; and

a Doppler frequency analyzer that performs Doppler frequency analysis with respect to the coherent integration result.

3. The radar device according to claim 1, wherein

a length of the second period has a variable length.

4. The radar device according to claim 3, wherein

the length of the second period varies depending on a directivity gain of a corresponding one of the transmission beams;

and

the second period has a longest length for a transmission beam in which the directivity gain is lowest out of the at least two transmission beams having different directions.

5. The radar device according to claim 3, wherein

in a case where the radar device is mounted in a vehicle, the length of the second period is longer for a transmission beam corresponding to a front direction of the vehicle than for a transmission beam corresponding to a lateral direction of the vehicle out of the at least two transmission beams having different directions.

6. The radar device according to claim 1, wherein

in a case where the radar device is mounted in a vehicle, the transmission beam controller adjusts number of the transmission beams included in each of the plurality of transmission beam sets in accordance with speed of the vehicle;

and

the number of the transmission beams in a case where the speed of the vehicle is equal to or lower than a predetermined threshold value is larger than that in a case where the speed of the vehicle exceeds the predetermined threshold value.

7. The radar device according to claim 1, wherein

in a case where the radar device is mounted in a vehicle, the transmission beam controller adjusts the number of the transmission beams included in each of the plurality of transmission beam sets and a length of the second period in accordance with speed of the vehicle;

the number of the transmission beams in a case where the speed of the vehicle exceeds a predetermined threshold value is smaller than that in a case where the speed of the vehicle is equal to or lower than the predetermined threshold value; and

the length of the second period in the case where the speed of the vehicle exceeds the predetermined threshold value is longer than in the case where the speed of the vehicle is equal to or lower than the predetermined threshold value.

8. The radar device according to claim 2, wherein

a length of the second period is equal to a multiplication result of the predetermined transmission period and an additional amount of the reflected signal in the coherent integration processor;

and

a length of the first period is equal to a multiplication result of the second period, the number of the transmission beams included in transmission beam set in the second period, and an additional amount of the coherent integration result in the Doppler frequency analyzer.